Sensitive and Selective Differential Pulse Voltammetry Detection of Cd(II) and Pb(II) Using Nitrogen-Doped Porous Carbon Nanofiber Film Electrode

Abstract

Carbon matrix materials are regarded as one of the most important electrode materials for heavy metal detection. But even so, optimization procedures of carbon nanofibers (CNFs) for tracing Cd(II) and Pb(II) remains challenging. Here, zeolitic imidazolate framework (ZIF-8)/polyacrylonitrile (PAN)-derived nitrogen-doped porous carbon nanofibers (N-PCNFs) were investigated as a new electrode material for determining the concentration of Cd(II) and Pb(II). By optimizing electrochemical conditions such as deposition potential, deposition time, pH of buffer solution, and quantity of N-PCNFs loaded on a glassy carbon electrode (GCE), the linear response curves of Cd(II) and Pb(II) could be obtained. Due to the unique structural feature and N content, the N-PCNFs possess excellent detection limits of 0.8 μg L −1 for Cd(II) and 0.3 μg L −1 for Pb(II) (S/N = 3). To manifest the practical use of the sensor platform the concentration of Cd(II) and Pb(II) in normal tap and waste water were monitored. According to the ICP-MS results, the calculated recovery (97.0-107%) indicates that N-PCNFs have potential as a candidate material to monitor the concentration of Cd(II) and Pb(II) in practical samples.

Recent Developments in Carbon Sensors for At-Source Electroanalysis

“…Nitrogen, sulfur, and oxygen functional groups are frequently used to create composite materials. , Examples of this include N-doped quantum dots, N,S-codoped porous nanofibers, and carbon nitride nanosheets ,, that have been designed for multielemental analysis in water sources. Gao et al improved sensitivity by using metal organic framework templates to create hollow, porous nanofibers, increasing the surface area of the N-doped carbon composite for Pb­(II) and Cd­(II) . Later in 2018, Gao et al created a combination composite of N,S-codoped porous nanofibers for Cd­(II) detection .…”

“…Gao et al improved sensitivity by using metal organic framework templates to create hollow, porous nanofibers, increasing the surface area of the N-doped carbon composite for Pb(II) and Cd(II). 110 Later in 2018, Gao et al created a combination composite of N,S-codoped porous nanofibers for Cd(II) detection. 107 Additionally, Manna et al showed that Sdoped porous GO exhibits excellent selectivity toward Hg(II) detection over other metal interferences.…”

Electrochemical Oxidation of Tannic Acid at ZIF-8 Induced Nitrogen Doped Porous Carbon Nanoframework Modified Electrode

“…Taking advantages of electrochemical detection techniques such as high accuracy, sensitivity and selectivity, [27][28][29][30][31][32] N-CNFs have been extensively explored for sensing and biosensing applications. [18][19][20][21][22][23][24][25][26] In the present work, a simple methodology of preparation of N-CNFs has been demonstrated using ZIF-8 as precursor (Scheme 1). Mesoporous silica (mSiO 2 ) protected calcination strategy has been applied to avoid the aggregation of nanoparticles during pyrolysis.…”

“…[14][15][16][17] On doping with different heteroatoms such as N, Co, P etc., carbon nanomaterials significantly modify their electronic, chemical and structural properties which allow their potential utilization in electrochemical applications. 3,[6][7][8][18][19][20][21][22][23][24][25][26] Different electronegativities in the doped carbon framework facilitate the electron transfer processes and hence the electrochemical performance of the carbon materials. The hierarchical structures of porous carbon improve the dispersibility of electrolytes = These authors contributed equally to this work.…”

Preparation of Electrochemical Sensor Based on RGO-Au-ZIF-8 Composite and Its Application in Simultaneous Detection of Lead Ions and Copper Ions

“…ZIF-8 [Zn(Hmim) 2 , Hmim＝2-甲基咪唑]是 ZIFs 中最具有代表性的一类材 料, 目前已经有将功能化的 ZIF-8 材料应用到重金属离 子电化学传感领域的报道. 例如, Gao 等 [25] 通过静电纺 丝法和碳化法合成了沸石咪唑酯骨架(ZIF-8)/聚丙烯腈 (PAN)衍生的氮掺杂多孔碳纳米纤维材料(N-PCNFs), 并采用差分脉冲阳极溶出伏安法(DPASV)实现了对实 际样品中 Pb 2＋ 和 Cd 2＋ 的同时检测. Xiao 等 [26] [26] , 晶体的尺寸大约为 100 nm.…”